1. Field of the Invention
The present invention relates to subsea manifolds, connectors, and pipeline end terminations (PLETS). More particularly, the present invention the relates to insulation assemblies suitable for application around the collet connection associated with such subsea apparatus. More particularly, the present invention the relates to latching mechanisms for allowing the insulation apparatus to be affixed around the collet connection.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
Technology advances related to subsea petroleum exploration have resulted in the development of various conduit and wellhead connector mechanisms which may be remotely controlled for the purpose of achieving connection between mechanical and hydraulic apparatus of wellheads, conduits, and the like. A popular type of connector assembly is a hydraulically-actuated collet connector which utilizes a series of segment clamps which are biased by various other mechanical apparatus to releasably secure a pair of abutting flanges into sealed assembly. Collet connectors and other acceptable connector mechanisms are generally utilized for connection of the wellhead valve system or the production system of the wellhead to lower wellhead structures so that the wellhead valve assembly may be disconnected and removed in the event that replacement or repair is necessary.
A multi-well subsea assembly can include subsea structures such as subsea trees, manifolds, and/or pipeline end terminations (PLETs). These subsea structures can be interconnected by jumpers. The jumpers mate up with the subsea structures using connectors that mate with hubs on the subsea structures. Production is often routed from the trees into gathering manifolds, and from the gathering manifolds to pipeline end terminations and pipelines to the platform.
As fluids flow from the subsea development toward the platform, the temperature of the fluids decreases, sometimes significantly, as heat is lost to the surrounding water. Measures are often taken to minimize heat lost and to keep fluid temperatures as warm as possible in order to maintain low viscosity and a proper flow of fluids within the pipelines. It is important to maintain the flow temperatures for the fluids in the event that production is shut down for any reason. In the absence of insulation, oil can slowly form hydrates at the various collet connections.
Typically, the pipeline and the piping in the PLETs, manifolds, trees, and jumpers are insulated so as to reduce heat loss to the surrounding seawater. Typically, the insulation is pre-installed on the piping before the structures are placed into the water.
The connectors on the ends of the jumpers, however, cannot be insulated prior to subsea installation. These connectors often have moving parts and mating surfaces which will require tools for installation. These features inhibit placing any sort of insulation upon the connectors. Insulation is often placed on the connectors after the connectors have been installed.
Current connector insulation systems use insulation that has been molded into a shape that conforms to the outer contours of a connector. The molded insulation may split into parts so that the insulation can be assembled upon the connector. This molded insulation can be in the form of pre-molded and/or rigid blocks. ROV's are often used to install this molded insulation upon the connector after the jumper is installed.
In the past, various patents have related to insulation systems for installation upon subsea structures. For example, U.S. Pat. No. 7,784,547, issued on Aug. 31, 2010 to S. K. Reddy, provides a subsea connector insulation device. This device has a frame coupled to and at least partially enclosing a subsea component. A bag is at least partially enclosed in the frame. The bag may substantially seal against at least one surface of the subsea component when the bag is at least partially inflated. A port is attached to the bag. The port allows the bag to be coupled to a fluid provider connector so that fluid can be provided into the bag to inflate the bag.
U.S. Pat. No. 7,823,643, issued on Nov. 2, 2010 to Wong et al., provides an insulation shroud with internal support structure. The insulation shroud includes a body adapted to be positioned around a subsea component. The body has an insulating material having an internal support structure positioned thereon, along with a door.
U.S. Pat. No. 8,006,763, issued on Aug. 30, 2011 to Bath et al., teaches a method and system for installing subsea insulation. This subsea insulation is installed on flowlines, connectors and other subsea equipment by a remotely operated vehicle. This system provides a mold designed and built to suit the parameters of the subsea item to be insulated. The mold is installed around the subsea item to be insulated and then injected with a liquid solution of insulation material. The liquid solution is then allowed to solidify so as to form a gel-molded insulation.
U.S. Patent Publication No. 2006/0266523, published on Nov. 30, 2006 to J. D. Lower, shows a subsea insulating shroud. This shroud is used to insulated a connector that connects a first tubular member having a first flange with a second tubular member that has a second flange. The apparatus has a generally tubular body forming a generally tubular cavity therein adapted to enclose the connector. The body has a longitudinal opening adapted to receive the first tubular member and a closure member for closing the opening. The body and the closure member are lined with insulation and include first and second seals for sealing with the first and second flanges so as to seal around the connector.
It is an object of the present invention to provide a collet connection insulation apparatus that provides insulation to the collet connection of a manifold or a PLET.
It is another object of the present invention to provide a collet connection insulation apparatus that maintains the temperature of the fluids flowing through the collet connection and avoids hydrate formations at the collet connection.
It is another object of the present invention to provide a collet connection insulation apparatus that is relatively inexpensive.
It is a further object of the present invention to provide a collet connection insulation apparatus that can be installed through the use of a remotely-operated vehicle.
It is a further object of the present invention to provide a collet connection insulation apparatus that can be effectively locked around the collet connection.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims.